public class car {
    private String pingpai;
    private Book book;

    public car() {
    }

    public car(String pingpai) {
        this.pingpai = pingpai;
    }

    public car(String pingpai, Book book) {
        this.pingpai = pingpai;
        this.book = book;
    }

    public car(Book book) {
        this.book = book;
    }

    @Override
    public String toString() {
        return "car{" +
                "pingpai='" + pingpai + '\'' +
                ", book=" + book +
                '}';
    }

    public Book getBook() {
        return book;
    }

    public void setBook(Book book) {
        this.book = book;
    }

    public String getPingpai() {
        return pingpai;
    }

    public void setPingpai(String pingpai) {
        this.pingpai = pingpai;
    }
}
